The engine immobiliser system is designed to prevent the vehicle from being stolen. This system uses a transponder key ecu that stores the key codes of authorized ignition keys. If an attempt is made to start the engine using an unauthorized key, the ecu sends a signal to the ecm to prohibit fuel delivery and ignition, effectively disabling the engine.

The transponder key coil receives this signal, the transponder key amplifier amplifies it, and then the signal is transmitted to the ecu. The ecu matches the key's id code with the vehicle's id code, which was previously registered in the ecu and then communicates the results to the ecm using sfi communication.
Engine immobiliser system
How to proceed with troubleshootingTerminals of ecu
Skid control ecu
Hint:
*1: W/ 16-inch disc
*2: W/ downhill assist control
*3: For 2wd (w/ auto lsd)
Check skid control ecu
Disconnect the a19 ecu connector.
Measure the voltage and resistance of the wire
harness side connector.
Hint:
The voltage cannot be measured ...
Diagnosis system
Description
Key reminder warning system data can be read
through the data link connector 3 (dlc3) of the
vehicle. When the system seems to be
malfunctioning, use the intelligent tester (with can
vim) to check for malfunctions and perform repairs.
Check dlc3
The vehi ...
Steering column assembly
Components
Removal
Caution:
Some of these service operations affect the srs airbag
system. Read the precautionary notices concerning the
srs airbag system before servicing the steering column
(see page rs-1).
Place front wheels facing straight ahead
Disconnect cab ...